Mechanically-playing keyed instrument.



PATENTED FEB. 25, 1908. I

F. MORITZ.

MEGHANIQALLY PLAYING KEYED INSTRUMENT.

APPLIOATION FILED MAR. 8, 1907.

WITNESSES INVENTOR A llama/.1

. nels in the tracker board require, in order to be the note band, aswell as the time v a certain length and corresponding admismuch longerare the note holes in the music single notes, it is much more the casewith a -nel openings to fill sufficiently and suddenly FRIEDRICH MORITZ,OF DORTMUND, GERMANY MECHANICALLY-PLAYING KEYED INSTRUMENT.

Specification of Letters Patent.

Patented Feb. 25, 1908.

Application filed March 8 1907- Serial No. 361.342.

To all whom it may concern:

Be it known that I, FRIEDRICH MoRITz, citizen of Germany, subject of theKing of Prussia and Emperor of Germany, residing at Dortmund, in theKingdom of Prussia and Empire of Germany, have invented certain new anduseful Im rovnients in Mechanio ally-Playing Keyer Instruments, of whichthe following is a full, clear, and exact description.

Piano playin apparatus, orchestrions and the like, when t ey work by airsuction, draw the air through suitable channels in a tracker board, overwhich a slotted note band ora band provided with holes is led. Thechanproduce the proper actionon the key board,

sion of air. The longer these channels are so sheet or band and also somuch longer must occupied in striking a note, which must be made asshort as possible. If thls is the case with series of notes followingquickly one after the other, trills and the like, and on account of thelarge amount of air, which is necessary for wide channels, especiallyalso with musical works having a large number of notes on a shortstretch of the note band, The drawbacks brought about by channels withlarge outlets are obviated by the present invention.

Figure 1 is a top view of the device applied to a mechanical pianoworking by suction. Fig. 2 is a transverse vertical section of thedevice as applied.

.In the drawings f and y designate respectively the rollers upon whichthe perforated music sheet 6 is Wound,said sheet passing over thetracker board (1, which islocated between the rollers f and 5 the latterbeing up erated in the usual and well known manner.

The long channels of the tracker board (I are covered at the top with ametal plate (1., which has the same number of openings c as the trackerboard although in the direction of the travel of the sheet e over thetracker board, they are kept as short as possible. In order to make itpossible for these short chanwith air, so that a short powerful blow canbe struck before each narrow channel opening a special inlet orpreliminary opening 0 is provided. This opening 7) is only made so largethat it alone, if the short channel opening is not yet uncovered by theholes in the note hand, does not allow enough air to enter to operatethe playing mechanism. Nevertheless this opening fulfils the nextcondition, namely that a vacuum no lon er exists in the previouslyevacuated channe s.

When now the note holes come over the preliminary'opening b they comenext over the short channel opening 0 and just at the time when thepreliminary opening also is still free. If the preliminary air hasalready fulfilled the condition of the change of air, the

.short channel opening which can be made so short that it alone evenwith powerful tread movement hardly produces any playing, is in theposition, in combination with the preliminary opening, to set theplaying apparatus in motion.

When the stroke or blow has been completed on account of the twoopenings, preiminary air opening and short channel'opening becominguncovered, the action thereby produced only lasts a short time, sincethe note band again covers the preliminaryair opening, and it of courseresults in withdrawal of the preliminary air, and also removal of thestriking ower. These preliminary air openings and short channel openingsarranged as above described make it possible to produce trills as wellas soft playing exactly as with the powerful tread movement. Further bythe provision of the preliminary air openings an economical consumptionof the quantity of air produced in playing is brought about. All thevariations, such as crescendo or decrescendo and toning of the singlenotes can be readily produced by the player. Moreover the player inworking the treads has not to apply any special power. 1 Owing to thewide channel openings of the previous arrangements, the note band wassucked firmly on to the slide block and there by braked or retarded sothat on operating the treads a great resistance had to be over come. Inthe present invention the powerful suction is completely avoided by theprovision of preliminary air openings since these small openings onlygive a small engagement surface on the note band. The consumption of airis also more economical. I

By means of the device set outin the ab e description a further drawbackis overcome,

which existed with the previous arrange-' ments, that the note band leftthe notes free to secure by Letters Patent is:

1. A tracker board having air channels and having a metal plate attachedto said tracker board over its air channels, said plate having main andsupplementary openings leading to the tracker board channels,a main anda supplementary opening leading to each tracker board channel,the mainopening in the plate being slits of least dimension in the direction oftravel of the sheet, and the supplementary openings in the plate beingarranged in advance of the main openings.

2. A tracker board having channels and main and supplementary 0 eningsleading to the tracker board channe sa'; main and a su plementaryopening leading to each channel-the main openings being slits of leastdimension in the direction of travel of the sheet, and the supplementaryopenings being arranged in advance of the main openings.

In witness whereof, I subscribe my signature, in presence of twoWitnesses.

FRIEDRICH MORIT Z. Witnesses:

OTTO KoNIG,

J. A. RITTERSHAUS.

